I have been wrestling with the original Qjet for months ...when i first put it on it ran like crap and leaked fuel at the top gasket and from the main discharge jets at idle...not good.

I decided to start from scratch and get all the right jets, rods, and gaskets for the carb. Cleaned it up and put it together. Thanks to Lars, I was able to gain insight and aquire the right intake to carb gaskets.

Once I did this, put the carb on and still a lot of the same issues.

Took it off, tinkered with it some more...put in the right power piston spring, bench tested the carb to make sure the power piston spring was working as advertised...the first one did not, the second and final spring worked like a champ.

During this whole process I was doing a lot of reading and talking to different folks. I learned that Qjets were very prone to airhorn warpage and that this can be the cause of much of my pain. So I spent some time drawing, cutting, grinding, and milling a jig that I could use to try to "flatten" out my airhorn ...did this and guess what??...the stinking airhorn no longer fit on the carb body!! so I spent some more time drawing, cutting, grinding, and milling a jig for the body of the carb and once I flattened out the surfaces of the carb the two pieces fit together like a glove. Having done all this I was now ready to get that bad boy back together and fire it up.

Well, I got it together and put it on the vette...the vette was very happy but the carb still had a very minor case of leakage on one side of the primary jets!

I am too much of a perfectionist to let this continue...so off with the Qjet and back on with the holley. As i looked at the Qjet some more and researched it some more, I realized that I had a slight difference in the gasket that goes between the carb base and body...so I found one i liked more from an old carb and put it on...guess what, no difference.

At this point i am a little frustrated, but not discouraged because the responsiveness of the qjet was all the motivation I needed...far better than anything the holley did for me...

Now for the ending...after sleeping on it, i thought...let me just go out there and tweak the air, fuel, and idle. When i did this I found the mixture to be too rich and as soon as i opened the leaking side a little, the leak stopped! unbelieveable to me! thats it?! I could have done that hours ago! So I set it properly and balanced the screws and seems to be fine...

anyway, I hope this info might help someone else out who might be struggling with a qjet. Mine looks, works, and responds like a champ now thanks to this forum and the info people like Lars put out there for the benefit of others. Hopefully I am done with the carb issues for a while.

 

 

inspiration for the rest of us.

 

Glad it worked out.

The air-horn "warps" because Bubba always overtitghtens the carb mount bolts.

I too love Q-jets. Doug Roe's Q-Jet book is a must if you're gonna poke at it,..money well spent.

 

Interesting post. Thanks for sharing and glad you got through it.

 

on the airhorn...later today I might post a before and after showing the warpage...pretty ugly

I have wanted that book...and obviously have needed it. I looked for it a couple of times in B&N and Books a million...havent come acrossed it yet.